Artificial leather.



S. TSCHOUMAKOFF.

ARTIFICIAL LEATHER.

APPLICATION FILED JULY 19, me.

1228.848. I Patenied 311m: 5, 19.17.

UNITED STATES PATENT OFFICE.

smou rsonomrnxorr, or rmnoem, iwssni.

ARTIFICIAL LEATHER.

specification of Letters latent. Patented June 5,1917.

Application filed Jul 19, 1am. serial in. 110,133.

To all whom it ma concern:

Be it known 1: at I, SIMON Tscnomm KOFF, a subject of the Emperor of Russia, and residing at Maxnnillanovsky Pereoulok 3, Petrograd, in the Empire of Russia,

have inyented certain new and usefnl Improvements in Artificial Leather, of which the following is a specification.

My invention relates to a new product of manufacture designed to replace the ordinary leather of animal origin. This product represents a leather of vegetable nature and isdistinguished by its main constitutive part being the outer layer of the birch-bark.

Any appropriate number of such outer layers of birch-bark are stuck together, the layers being disposed in such a manner that the direction of the lenticels (i. e. the small elongated spots penetrating such layers cross themselves at rlght angles in alternate layers, and such alternate layers being separated from each other byinter'posixig one sheet'of cotton stufi' (canvas) or the like.

The characteristicfeatures of such leather of vegetable nature (which I propose to designate by the name Betuladerma) consist in that such leather, owing to its being coniposed mainly of sheets of the outerlayer of irch-bark, which generally contains about 50% of oily-resinous matters, has the prop erty of not being moistened by water and being impermeable to the latter, this property, in addition to the elasticity andrel'atively considerable tensile strength and resistance against punctures, permitsthe use of such an artificial leather in lieu of the ordinary leather of animalvorigin (the sole leather, of course, excluded) or of rubbered fabrics.

In 7 the accompanying figure of draw ng illustrating the invention a designates a bottom layer or sheet of the outer layer ofbirch bark, the lenticels a" of which, shown in dotted lineslrun transversely of the sheet.

A superimposed layer of textilefabric 1b or,

being arranged at right angles to the lentieels of the other piece.

I u witness whereof I have hereunto set my hand in presence 01' two witnesses.

SlMUN 'lSCl-IOUMAKOFF. \Yiti nesses:

H. A. Lovnoum s, AUG. Miouis. 

